Learn to Use a Refractometer (Video)
This refractometer tutorial video will show you how to find a gem’s refractive index, birefringence, optic character, and other properties.…
This refractometer tutorial video will show you how to find a gem’s refractive index, birefringence, optic character, and other properties.…
Learning how to conduct a gemstone examination takes practice. Follow an expert gemologist step-by-step through tests of five unknown samples.…
Although you can’t weigh a gemstone in a jewelry setting, you can get a close approximation of the gem weight by determining its volume.
Measuring “over the limit” (OTL) refractive indices can help distinguish diamonds from simulants. You can do this with a simple upgrade to…
Learn how gems absorb wavelengths of light and how gemologists use gemstone absorption spectra to identify gems. There’s more to color than…
Sometimes, microscopic inclusions are the only way to distinguish natural from synthetic gems. This makes the microscope an essential lab instrument…
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